Microscope optics

Size and Shape. The dimensions of the standard are more critical In the microenvironment than In the macroenvironment, since microscopic measurements commonly require changes In field apertures and magnification. If a microscopic standard has a small (/im-slzed), well-defined shape, such as a sphere or cylinder, an accurate Intensity/ volume relationship can be established, which should be Independent of the microscope optics. Standardization Is thus valid no matter what microscope parameters are employed, as long as the spectral characteristics of the standard and the sample are quite similar or Identical. 

De Martini, F., Innocenti, G., Jacobovitz, G.R. and Mataloni, P. (1987) Anomalous spontaneous emission time in a microscopic optical cavity. Phys. Rev. Lett., 59, 2955-2958. 

Mass spectrometric measurements of ions desorbed/ionized from a surface by a laser beam was first performed in 1963 by Honig and Woolston [151], who utilized a pulsed mby laser with 50 p,s pulse length. Hillenkamp et al. used microscope optics to focus the laser beam diameter to 0.5 p,m [152], allowing for surface analysis with high spatial resolution. In 1978 Posthumus et al. [153] demonstrated that laser desorption /ionization (LDI, also commonly referred to as laser ionization or laser ablation) could produce spectra of nonvolatile compounds with mass > 1 kDa. For a detailed review of the early development of LDI, see Reference 154. There is no principal difference between an LDI source and a MALDI source, which is described in detail in Section 2.1.22 In LDI no particular sample preparation is required (contrary to... 

Fig. 6 (a) Schematic illustration of a flow cytometer used in a suspension array. The sample microspheres are hydrodynamically focused in a fluidic system and read-out by two laser beams. Laser 1 excites the encoding dyes and the fluorescence is detected at two wavelengths. Laser 2 is used to quantify the analyte, (b) Scheme of randomly ordered bead array concept. Beads are pooled and adsorbed into the etched wells of an optical fiber, (c) Scheme of randomly-ordered sedimentation array. A set of encoded microspheres is added to the analyte solution. Subsequent to binding of the analyte, microparticles sediment and assemble at the transparent bottom of a sample tube generating a randomly ordered array. This array is evaluated by microscope optics and a CCD-camera. Reproduced with permission from Refs. [85] and [101]. Copyright 1999, 2008 American Chemical Society... 

N. (1985) Three-dimensional microscopy using a confocal laser scanning microscope. Optics Lett. 10, 53-55. 

Enhancement of the Hght-matter interaction in a microscopic optical cavity is achieved because Hght trapped in the cavity has longer effective interaction time with absorbers. For short laser pulses, cavity length exceeding CTp allows avoidance of the interference between the pulses incident and reflected from the mirrors. Spectral selectivity of planar Fabry-Perot cavities can be used to achieve the localization at the resonant wavelength of the cavity. 

A solution of brain lipids was brushed across a small hole in a 5-ml. polyethylene pH cup immersed in an electrolyte solution. As observed under low power magnification, the thick lipid film initially formed exhibited intense interference colors. Finally, after thinning, black spots of poor reflectivity suddenly appeared in the film. The black spots grew rapidly and evenutally extended to the limit of the opening (5, 10). The black membranes have a thickness ranging from 60-90 A. under the electron microscope. Optical and electrical capacitance measurements have also demonstrated that the membrane, when in the final black state, corresponds closely to a bimolecular leaflet structure. Hence, these membranous structures are known as bimolecular, black, or bilayer lipid membranes (abbreviated as BLM). The transverse electrical and transport properties of BLM have been studied usually by forming such a structure interposed between two aqueous phases (10, 17). 

The apparatus consists of a microscopic optical system, a grating mirror combination (Fig. 1A, IB) for spectral and topographic measurement, and an optical multichannel analyzer (OMA) equipped with a silicon intensified tube (SIT) as a photon detector (55). 

D. Microscopic optical arrangement centered around the Leitz-Diavert inverted microscope... 

Figure 1. UV field illumination of a Plan Apo 100x lens (1.4 NA) derived with a fluorescent plastic slide and the intensity measurement of 10-micron Spherotech beads (obtained from Spherotech, Libertyville, IL, USA). This illustrates the problem of using a lens with improper field illumination to make comparative measurements on a sample. The field illumination pattern shows a bull s eye intensity pattern slightly off-center and the five beads located in different parts of the field to illustrate the variation in intensity occurring by using a lens that has improper field illumination. The intensity of beads was derived by a small Region of Interest (ROI) inside the bead. The five beads show a decrease in intensity relative to the bead in the center of the illumination. Although this figure was obtained with UV optics, it represents the type of field illumination that can also occur with visible light excitation. This pattern is also unacceptable, if a confocal laser scanning microscope optical system is used for a FISH study, as the maximum intensity should be in the center of the objective and not in the corner.

ST Microscope Scanning Electron Microscope Optical Microscope... 

Electron diffraction data collection involves the required microscope optical alignment and special attention to the sample position, sample thickness and rotation, diffraction CL and diffraction lens focusing, and the detector used to record electron diffraction patterns. The CL is determined by the projection lenses in combination with the objective lens (the first lens after the specimen). To use the calibrated CL, the sample position and the objective lens setting must be the same setting between the calibration and experiment. 

Carlsson, K., Danielsson, P. E., Lenz, R., Liljeborg, A, Majlof, L., and Aslund, N. (1985) Three-dimensional microscopy using a confocal laser scanning microscope Optics Lett 10,53-55. 

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